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制备了CeO2-Zr02-La203/Al2O3材料,在制备过程中使用超声波振动对材料进行处理,并以此材料为载体制备了单Pd三效催化剂.对所制备的载体进行了织构性能分析(BET)和X射线衍射(XRD)表征.对催化剂进行了NO程序升温脱附(NO-TPD)及H2程序升温还原(H2-TPR)表征,并对催化剂进行了活性测试.BET结果表明,900℃焙烧后,超声波振动处理的载体比表面积为130m2·g-1,而没有进行处理的载体比表面积为117m2·g-1.超声波处理的CeO2-ZrOrLa203/Al20s材料介孔直径为11.4nm,相对较大,载体更加稳定.XRD测试结果表明,超声波处理的载体在1150℃焙烧5h后仍然只有Ce0.5Zr0.5O2一个单一物相,而未经过超声波处理的载体此时出现相分离,体相中有θ-Al2O3出现.以超声波处理材料为载体的Pd催化剂新鲜和老化后NO-TPD测试结果变化很小.H2-TPR测试中,超声波振动处理的材料制备的催化剂中活性组分和载体的还原峰温较未超声处理材料制备的催化剂稍高,而峰面积远大于未超声处理材料制备的催化剂.活性测试结果说明,由超声波振动处理过的载体制备的三效催化剂对汽车尾气中的三种污染物的起燃温度更低,有更好的活性以及温度特性.
The material of CeO2-ZrO2-La2O3 / Al2O3 was prepared and treated by ultrasonic vibration in the process of preparation, and the single-Pd three-way catalyst was prepared on the basis of this material.The texture properties of the prepared support were measured by BET ) And X-ray diffraction (XRD) were used to characterize the catalyst.The NO-TPD and H2-TPR were used to characterize the catalyst and the activity of the catalyst was tested.The results of BET showed that the temperature of 900 ℃ After roasting, the specific surface area of the carrier treated by ultrasonic vibration was 130m2 · g-1, while that of the untreated carrier was 117m2 · g-1. The mesoporous diameter of the sonicated CeO2-ZrOrLa203 / Al20s was 11.4nm, XRD test results show that after sonicating the carrier calcined at 1150 ℃ for 5h, there is still only a single phase of Ce0.5Zr0.5O2, while the carrier without ultrasonic treatment appears phase separation, the bulk phase has θ-Al2O3 appeared.The results of NO-TPD test of fresh and aged Pd catalysts with sonication material as carriers varied little.H2-TPR test showed that the reduction peak of active components and carriers in the catalyst prepared by ultrasonic vibration treatment Temperature is not The results showed that the three-way catalyst prepared by the ultrasonic vibration-treated carrier had a good effect on the three pollutants in the vehicle’s tail gas Burning temperature is lower, with better activity and temperature characteristics.